I was doing questions in the Trigonometry and I came across this question at the bottom of the page, I dont know what to do, please help.

"Find out what road gradients suck as '1 in 10' mean, Use trigonometry to work out the angle of the slope of different gradients"

Please help.

## Answers (2)

yeah using that logic

the angle is defined by tan x=1/10

so arctan(1/10) = x

which is .0997 degrees ~.1

it means the distance the road rises (or falls). 1 in 10 mean the road rises 1 unit for each 10 you travel along.

1 in 15 would mean the road rises one meter in height every 15 meters travelled. You can think of it like a triangle to work out the angle.